The collection consists of two series:

"H.T. Colebrooke - Memoirs and Autographs", A red calf bound book, containing printed and handwritten material including biographical material concerning Colebrooke, obituary notices for Horace Hayman Wilson, and correspondence from Colebrooke to Nathaniel Wallich. On the inside cover there is a bookplate with "Ex Libris Frederick Hendricks, F.S.S., F.S.A., Knight of Vasa. 1893" and a printed auction listing "226. Colebrook (H.T.) Notice historique sure la vie et les ouvrages de M. Colebrooke par M. C.A. Walckenaer, Paris, 1848, with biographical notices from various periodicals and numerous interesting autograph letter of Colebrooke, half red calf". Frederick Hendricks is an ancestor of the donor who also has family connections with the Colebrooke family.

Newspaper cutting for the sale of three items of correspondence from Henry Thomas Colebrooke to Dr Wallich dating from 1823-1837. Written in pencil beside the cutting, "Autograph Letters of Colebrooke, Wallich's Catalogue"

"Extracts of three letters from Mr. H. Colebrooke to Dr. W. Carey". These concern the appointment of Dr Wallich at the Botanic Gardens and are dated 6th January, 13 January and 26 January, 1817. At first Colebrooke would not recommend Wallich because he thought another eminent botanist had been appointed but on discovering that this botanist had no wish to travel to India, Colebrooke and Dr Fleming petitioned the Court of Directors, East India Company, with the support of Sir Joseph Banks, for Wallich to be appointed to the role. Handwritten, copied by unknown hand.

"Extract from a General Letter from the Honb. Court of Directors, dated the 13th February 1817". This confirms the Court of Directors' agreement to appoint Dr Wallich as Superintendent of the Botanical Gardens. Handwritten by unknown hand.

Letter from Henry Thomas Colebrooke to Nathaniel Wallich, pleased to hear that Wallich has resumed his role at the Botanic Gardens and thanking Wallich for his responses to Colebrooke's previous inquiries. He thanks Wallich also for sending seeds and that the plants that he sent are doing well at Kew. He asks if more can be sent. Wallich will be proposed for the Linnean Society after the Easter break and can also be proposed to the Geological Society. Colebrooke is keen to promote study on the geology of India and states information that he would like to collect. Colebrooke is pleased that Wallich is in contact with Mr Alexander of the Cape of Good Hope. He is also contemplating whether the "Gayal" would be suitable cattle for Cape of Good Hope and England and is looking into the possibility of shipping some heifers and steers. Handwritten, dated 18 March 1818, with Wallich's dating, arrived 28 July by Marchioness of Ely, answered 29 July by [Oriton]

Letter from Henry Thomas Colebrooke to Nathaniel Wallich in which Colebrooke thanks Wallich for his correspondence and the seeds he has sent. The one that Wallich has sent for the Botanic Garden at Copenhagen he has given to Dr Fleming to take. Colebrooke encourages Wallich to write to Fleming as Fleming was instrumental in Wallich keeping his position at the Botanic Garden. He reiterates his desire for Wallich to send living plants. Colebrooke also thanks Wallich for geological specimens and gives instructions as to how to package them correctly. Wallich has been proposed for the Linnean Society which will meet some weeks after the letter's date. Handwritten, dated 15 April, 1818 with further dating in Wallich's hand arrived 24 October.

Letter from Henry Thomas Colebrooke to Nathaniel Wallich in which he thanks Wallich for Nepal seeds and for rock specimens sent to him. He gives details of how various seeds and plants are growing in England mentioning Sir Joseph Banks and Mr Lambert. Wallich has been elected to the Linnaean and Geological Societies. Colebrooke will pay his fees if Wallich will reimburse to Colebrooke's agent. Colebrooke thanks for interesting papers that Wallich has sent including Captain Webb's account concerning the Himalayan mountains. Handwritten, dated 22 April 1819, dated in Wallich's hand, received 8 October.

Letter from Henry Thomas Colebrooke to Nathaniel Wallich in which he thanks Wallich for his correspondence and specimens, and congratulates him on his progress in natural history. Colebrooke suggests a name for a plant that he has described and in the post script reflects and changes the name. He advises pursuing certain avenues in research. Colebrooke encloses a receipt for Wallich's fee for the Linnaean Society (not with letter). Handwritten, dated 8 June 1819, received 16 November 1819.

Letter from Henry Thomas Colebrooke to Nathaniel Wallich in which he thanks Wallich for his correspondence and his Geological and Botanical Despatches and for Mr D Scott's remarks. He enquires whether Scott would like to be a member of the Geological Society. He writes of Limestone specimens that Wallich sent and of that he is pleased that the Gayal cattle have not been sent. He suggests that Wallich might write to his relative, Mr James Gosling, at the Cape of Good Hope who would be happy to try any specimens in his garden that Wallich thinks could flourish there. He asks about various species and botanical drawings. Handwritten, dated 8 September 1819, received 16 March 1820.